Fluid supply systems in industrial, residential, and commercial environments often include one or more accumulator tanks for insuring that the flow rate and pressure of fluid supplied to various locations is substantially steady. Some accumulator tanks contain a reservoir of fluid that can be supplied to the system at peak demand times in order to maintain a substantially steady fluid flow rate and pressure. At times of lower demand, the fluid supply system can replenish such accumulator tanks with fluid.
Accumulator tanks typically include a rigid outer shell having a single aperture through which fluid can flow to and from the fluid supply system. Accumulator tanks also typically include a flexible bladder made from a porous material, such as butyl rubber, positioned within the rigid outer shell. This flexible bladder also has a single aperture aligned with the aperture in the shell and through which fluid can flow to and from the fluid supply system. Fluid enters and exits the bladder through the aligned apertures, and does not contact the rigid outer shell of the accumulator tank. In order to permit bladder expansion and contraction as fluid enters and exits the accumulator tank, respectively, conventional accumulator tanks often include one or more air holes through the rigid outer shell.
During extended periods of low demand, fluid can remain in the bladder of an accumulator tank for relatively long periods of time. Also, deposits from the fluid can collect within the bladder and can adhere to the internal walls of the bladder (e.g., retained within pores of the rubber material). The tendency of such deposits to accumulate within the bladder increases the difficulty of maintaining clean and sanitary conditions within the accumulator tank.